Keep hidden local variables when dumping and loading iseqs

Fixes [Bug #19975]

1 files changed, 17 insertions, 0 deletions

diff --git a/test/ruby/test_iseq.rb b/test/ruby/test_iseq.rb
index 9b584c540c..ebb28af116 100644
--- a/test/ruby/test_iseq.rb
+++ b/test/ruby/test_iseq.rb
@@ -566,6 +566,23 @@ class TestISeq < Test::Unit::TestCase
     iseq2
   end
 
+  def test_to_binary_with_hidden_local_variables
+    assert_iseq_to_binary("for foo in bar; end")
+
+    bin = RubyVM::InstructionSequence.compile(<<-RUBY).to_binary
+      Object.new.instance_eval do
+        a = []
+        def self.bar; [1] end
+        for foo in bar
+          a << (foo * 2)
+        end
+        a
+      end
+    RUBY
+    v = RubyVM::InstructionSequence.load_from_binary(bin).eval
+    assert_equal([2], v)
+  end
+
   def test_to_binary_with_objects
     assert_iseq_to_binary("[]"+100.times.map{|i|"<</#{i}/"}.join)
     assert_iseq_to_binary("@x ||= (1..2)")